[Fat Bear Science] When you scream in pain, should you take painkillers or not? Experts say we need to understand cancer pain scientifically

Cancer pain has always been a major problem that plagues cancer patients and is also one of the most common symptoms of cancer patients. Cancer pain, also known as cancer pain, is generally divided into pain caused by tumors invading various nerves and organs or local tumor necrosis, ulcers, inflammation, etc. and pain caused during tumor treatment such as surgery, chemotherapy, radiotherapy, etc.

Clinically, nearly 60% of cancer patients have persistent or frequent cancer pain, of which 30% are severe and intense pain, and 70% of cancer patients do not receive standardized treatment, which seriously affects the quality of life of patients. Among them, some patients have poor results or intolerance adverse reactions after conventional drug treatment, resulting in refractory pain, such as cancer breakthrough pain, bone metastasis cancer pain, cancer neuropathic pain, etc.

Cancer pain is a common problem worldwide. Statistics from the World Health Organization show that one million cancer patients in China suffer from cancer pain every day.

Cancer pain patients are often accompanied by negative emotions such as anxiety and depression, which may lead to patients resisting anti-tumor treatment and even leading to suicidal thoughts. Therefore, scientific understanding and standardized treatment of cancer pain are of great significance.

On October 26, the first Yangtze River Palliative Care Summit Forum, hosted by Chongqing Association of Integrated Traditional Chinese and Western Medicine and organized by the Affiliated Cancer Hospital of Chongqing University, was held in Hechuan District.

At this forum, relying on the "Standardized Diagnosis and Treatment Demonstration Base for Refractory Pain", the Affiliated Cancer Hospital of Chongqing University initiated and jointly established the "Standardized Diagnosis and Treatment Consortium for Refractory Pain" with 17 medical institutions including Chongqing Hospital of Traditional Chinese Medicine, Three Gorges Central Hospital, Qianjiang District Central Hospital as collaborative units, and in cooperation with grassroots hospitals.

Today, let’s talk about how to scientifically understand cancer pain and painkillers, as well as some misunderstandings that the public has about painkillers.

Yu Huiqing, chief physician, postgraduate tutor, director of the Department of Palliative Care/Pain Center of the Affiliated Cancer Hospital of Chongqing University, is good at diagnosing and treating lung cancer, colorectal cancer, gastric cancer, liver cancer, lymphoma and other diseases, especially chemotherapy, molecular targeted therapy, biological immunotherapy, cancer pain, tumor nutrition and other therapies.

Outpatient clinic: Monday morning and Wednesday morning

Wang Sixiong, Doctor of Medicine, is an associate chief physician of the Department of Palliative Medicine/Pain Center of the Affiliated Cancer Hospital of Chongqing University. He specializes in chemotherapy and targeted therapy for malignant tumors such as lung cancer, colorectal cancer, liver cancer, gastric cancer, esophageal cancer, sarcoma, standardized diagnosis and treatment of cancer pain, and nutritional support and palliative care for patients with malignant tumors.

Outpatient clinic: Thursday afternoon and Friday afternoon

01

Cancer pain can be divided into three categories

■ Pain caused by the tumor itself. The tumor invades and compresses blood vessels, nerves, internal organs, and bones. For example, tumors invade the pleura and cause chest pain, metastasize to the lumbar spine and cause back pain, metastasize to the brain and cause headaches, such as nasopharyngeal carcinoma invading and compressing the cervical nerves and causing neck and shoulder pain, such as gastric cancer metastasis to the abdominal lymph nodes and compressing the abdominal nerves and causing abdominal pain, etc.

■ Tumor-related pain. This refers to pain caused by complications related to the tumor, such as pain caused by malignant intestinal obstruction caused by colorectal cancer blocking the intestines, and pain caused by pathological fractures caused by tumor bone metastasis.

■ Pain related to tumor treatment, such as pain caused by local organ adhesion, nerve damage, scars, etc. after surgery, and pain caused by stomatitis, hand and foot ulcers, and neuropathy at the end of the fingers caused by chemotherapy drugs and targeted drugs.

02

The pain becomes unbearable when it reaches moderate level

The assessment of cancer pain is mainly based on the patient's subjective feelings, and the pain severity can be divided into four levels: no pain, mild pain, moderate pain, and severe pain.

A numerical method can also be used, with a range of 0 to 10, with 0 indicating no pain, 10 indicating the most severe pain the patient can imagine, 1 to 3 indicating mild pain, 4-6 indicating moderate pain, and 7-10 indicating severe pain. Mild pain means the pain is tolerable and does not affect sleep and work, moderate pain means the pain is unbearable and affects sleep and work, requiring analgesic treatment, and severe pain means that sleep is seriously affected and may be accompanied by sweating and irritability, requiring immediate analgesic treatment.

03

Classification of cancer pain medications

Cancer pain relief drugs are mainly divided into three levels of analgesics: non-opioid drugs, weak opioids, strong opioids, and auxiliary analgesic drugs.

■ First-tier drugs

Non-opioid drugs are non-steroidal analgesics, including ibuprofen, acetaminophen, diclofenac, aspirin, celecoxib, naproxen, etc. They mainly have antipyretic, analgesic and anti-inflammatory effects and can be used for mild pain. The main side effects include gastric and duodenal ulcers and bleeding, liver and kidney damage, etc.

■ Second-tier drugs

Weak opioids. Including codeine, rofencodeine sustained-release tablets, codeine aminophenazone, dihydrocodeine, tramadol, hydroxycodone aminophenazone and other drugs, used for moderate cancer pain, its main side effects are dizziness, nausea, constipation and so on.

■ Third-tier drugs

Strong opioids. Including morphine hydrochloride sustained-release tablets, morphine hydrochloride tablets, oxycodone sustained-release tablets, fentanyl transdermal patches, pethidine (pethidine), methadone, etc., used for severe cancer pain, common side effects include dizziness, nausea, constipation, sedation and drowsiness, dysuria, etc.

■ Auxiliary analgesics

Including hormones. Such as dexamethasone and prednisone, which can relieve pain caused by tumor compression of nerve edema, antidepressants such as doxepin and amitriptyline, which can calm and improve mood, and anticonvulsants such as carmozepine and phenytoin sodium, which can assist in improving pain caused by chemotherapy and radiotherapy. These auxiliary analgesics can enhance the effect of analgesics, reduce the dosage of analgesics, and thus reduce the side effects of analgesics.

04

Cancer pain analgesia treatment mainly follows five treatment principles

■ Take the medicine orally whenever possible

For patients who can eat, oral administration is convenient, non-invasive, and easy to use for a long time. It is suitable for most patients, but not for patients with dysphagia such as esophageal cancer or pyloric obstruction, nor for patients who cannot eat due to intestinal obstruction. Such patients can use external fentanyl transdermal patches or give painkillers through the skin or intravenous routes.

■ Administer medication on time

After oral analgesics enter the human body, they produce analgesic effects after reaching a certain concentration in the blood. However, as time goes on, the drug concentration will gradually decrease and the analgesic effect will weaken accordingly. Therefore, it is necessary to take the medicine on time to ensure that the drug maintains a certain concentration in the blood to achieve the best analgesic effect.

■ Step-by-step dosing

Generally speaking, when a patient is diagnosed with cancer pain for the first time, the pain score can be classified as mild, moderate or severe, and the first, second or third step analgesic drugs can be selected respectively. If the patient is experiencing cancer pain for the first time and the pain is mild, first step drugs such as ibuprofen, diclofenac, etc. can be started.

If the initial diagnosis of cancer pain is moderate cancer pain, second-step tramadol sustained-release tablets, hydroxycodone acetaminophen, codeine and other drugs can be given. If the initial diagnosis of cancer pain is severe cancer pain, strong opioid drugs such as morphine hydrochloride sustained-release tablets can be given for treatment.

For moderate to severe cancer pain, the current analgesic regimen does not recommend the use of second-tier drugs as the first choice, but instead emphasizes the use of strong opioids such as morphine hydrochloride as the first choice for analgesic treatment.

■ Personalized medication

Each patient has a different sensitivity to analgesics. During analgesic treatment, painlessness should be the best treatment goal based on the individual patient's condition. Excessive concern about drug side effects leading to insufficient medication, which would affect the effectiveness of analgesic treatment, should not be tolerated.

■ Pay attention to details and effects

During analgesic treatment, while ensuring the analgesic effect, the adverse reactions of analgesics must be closely observed and dealt with in a timely manner. The purpose is to enable patients to benefit from analgesic treatment to the greatest extent possible.

05

Misunderstandings of the public about painkillers

Analgesics are an important means of treating cancer pain, but the public has more or less some misunderstandings about the use of analgesics, such as the following common misunderstandings about analgesics:

public

Opioids such as morphine are only used when the patient is in the most severe pain.

wrong!

doctor

For cancer pain, standardized and timely use of analgesics can achieve the best analgesic treatment effect. Ordinary analgesics cannot relieve the patient's pain, but will only make the patient suffer from the pain caused by cancer for a longer time. At this time, a smaller dose of morphine can be selected to enable the patient to quickly relieve the pain.

The degree of cancer pain has no direct relationship with the stage of cancer and the severity of the disease. It is related to the range of the tumor, invasion of nerves and surrounding tissues, and the site of metastasis. Therefore, severe pain does not represent the severity of the disease.

public

Opioids such as morphine can be addictive after long-term use.

wrong!

doctor

Studies have shown that the risk of addiction (psychological dependence) caused by long-term, standardized use of opioids for analgesic purposes is extremely small, because the long-term, standardized, and regular use of opioid sustained-release and transdermal analgesics keeps their concentrations in the blood at a stable level and does not result in excessive concentrations in the blood, reducing the risk of addiction.

public

Once you start using opioids, you will need to take them for life.

wrong!

doctor

The treatment of tumors is a comprehensive treatment. During the use of opioid analgesics, if the patient's pain is relieved after chemotherapy, radiotherapy, targeted therapy and other anti-tumor treatments, the dose of opioids can be safely reduced at any time until the drug is stopped, or downgraded to non-opioid analgesics. However, it should be noted that the process of reducing the dose until the drug is stopped needs to be carried out gradually and slowly to avoid withdrawal symptoms.

public

Non-opioid medications have a better safety profile than opioids.

wrong!

doctor

For patients with moderate to severe cancer pain, long-term use of opioids for analgesia is safer because opioids have fewer side effects on liver and kidney function and the digestive tract. However, it should be noted that large doses may affect respiratory function, but as long as they are used in a standardized manner, the risk of respiratory depression is very small.

However, during long-term use, non-opioid drugs may cause serious adverse reactions such as gastrointestinal bleeding, liver and kidney damage, and thrombocytopenia. Therefore, non-opioid drugs are not as safe as opioid drugs.

public

Analgesic treatment can provide partial relief to the patient.

wrong!

doctor

The purpose of cancer pain treatment is to relieve the patient's pain to the greatest extent, ensure sleep and rest, improve the patient's mood, and at the same time ensure the smooth progress of anti-tumor treatment. Painless sleep is the minimum goal of analgesic treatment. By relieving cancer pain to the greatest extent, the patient's quality of life can be greatly improved.

public

Opioids should be discontinued if side effects such as vomiting and dizziness occur.

wrong!

doctor

Nausea, vomiting, and dizziness are common adverse reactions to opioids, but these adverse reactions are often temporary. They usually occur within the first few days of use, but most of them will disappear on their own after a few days. For these adverse reactions of opioids, publicity and education can be carried out, and preventive treatment can be carried out when necessary to alleviate these adverse reactions.

public

Demerol is a safer pain reliever than morphine.

wrong!

doctor

Currently, the World Health Organization no longer recommends the use of pethidine to treat cancer pain, because pethidine's potency is one-tenth that of morphine, it has neurotoxic and nephrotoxic properties, its oral utilization rate is poor, and its intramuscular injection is its only method of administration, which itself causes pain to the patient. Long-term injection may lead to infection, subcutaneous nodules, nerve damage and other adverse consequences.

Text/Fat Bear Photos/Internet (Please contact to delete) Review/Yu Huiqing Wang Sixiong

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